When assessing modern automatic dishwashing agents, the consumer's interest is centered both on the performance aspects of these agents, in other words their cleaning and rinsing performance in particular, and on their manageability.
One of the principal objectives of manufacturers of automatic dishwashing agents is to improve the cleaning and rinsing performance of these agents, with greater focus being placed in recent times on cleaning and rinsing performance in low-temperature wash cycles and in wash cycles with reduced water consumption.
Typical presentation forms for dishwashing agents include in addition to traditional liquid washing-up liquids in particular also automatic dishwashing agents which are marketed predominantly in solid form and which are available for example as powders or tablets. These known packaging and presentation forms are however constantly undergoing new changes. A primary focus of attention in recent times has been the simplified dosing of automatic dishwashing agents.
In this context product developers have in recent times begun to turn their attention for example to devices for the multiple dosing of washing and cleaning agents. A distinction can be made with these devices between dosing containers which are integrated in the automatic dishwasher or washing machine on the one hand and standalone devices which are independent from the automatic dishwasher or washing machine on the other. By means of these devices, which contain multiples of the amount of cleaning agent necessary for one cleaning process, portions of washing or cleaning agent are dosed automatically or semi-automatically into the interior of the washing appliance during the course of several successive cleaning processes. For the consumer this eliminates the need to keep manually adding the washing and cleaning agents. Examples of such devices are described in the European patent application EP 1 759 624 A2 (Reckitt Benckiser) or in the German patent application DE 10 2005 062 479 A1 (BSH Bosch and Siemens Hausgeräte GmbH).
Irrespective of the precise construction of the dosing devices used in the interior of automatic dishwashers or washing machines, the washing or cleaning agents contained in these devices for multiple dosing are exposed in particular to fluctuating temperatures over an extended period of time, these temperatures being similar in a first approximation to the water temperatures used for the washing or cleaning processes. These temperatures can be up to 95° C., although temperatures of only between 50 and 75° C. are conventionally reached in automatic dishwashing. Accordingly, during the course of several washing or cleaning processes, a washing or cleaning agent contained in a device designed for multiple dosing is repeatedly heated to temperatures well above the conventional transport and storage temperatures, with heat-sensitive active substances being affected in particular. This group of heat-sensitive active washing and cleaning substances primarily includes active washing and cleaning enzymes.
A range of different protective measures have been proposed to increase the stability of such enzyme-containing liquid washing or cleaning agents. Thus for example the German patent application DE 2 038 103 (Henkel) teaches the stabilization of enzyme-containing automatic dishwashing agents with saccharides, while propylene glycol for enzyme stabilization in liquid cleaning agents is disclosed in the European patent EP 646 170 B1 (Procter & Gamble).
Accordingly, it is desirable to provide an automatic dishwashing agent which is stabilized to prevent phase separation/loss of activity under repeated temperature fluctuations (10 to 75° C.), and which can be stored in a supply device located in the interior of an automatic dishwasher with no significant loss of activity. In addition, it is desirable to provide an automatic dishwashing agent that has an improved performance profile in comparison to conventional automatic dishwashing agents. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the background of the invention.